A large number of transition metal complexes have been reported, which can be used in asymmetric syntheses such as asymmetric hydrogenation reaction, asymmetric isomerization reaction and asymmetric hydrosilylation reaction. Particularly, a complex in which an optically active tertiary phosphine compound is coordinated to a transition metal complex such as of ruthenium, rhodium, iridium or palladium has excellent performance as a catalyst of asymmetric synthesis reactions.
In order to further improve this performance, a large number of phosphine compounds having various structures have so far been developed (Chemical Review 32 "Chemistry of Organic Metal Complex", pp. 237-238, 1982, edited by The Chemical Society of Japan; "Asymmetric Catalysis In Organic Synthesis", edited by R. Noyori, A Wiley-Interscience Publication).
Particularly, 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (to be referred to as "BINAP" hereinafter) is one of the excellent optically active phosphine compounds, and a rhodium complex (JP-A-55-61973; the term "JP-A" as used herein means an "unexamined published Japanese patent application") and a ruthenium complex (JP-A-61-63690), which contain the BINAP as a ligand, have already been reported.
Also, it has been reported that a rhodium complex (JP-A-60-199898) and a ruthenium complex (JP-A-61-63690), which contain 2,2'-bis(di-(p-tolyl)phosphino)-1,1'-binaphthyl (to be referred to as "p-TolBINAP" hereinafter) as a ligand, give good results in asymmetric hydrogenation reaction and asymmetric isomerization reaction. In addition, it has been reported in JP-A-3-255090 that a ruthenium complex of 2,2'-bis(di-(3,5-dialkylphenyl)phosphino)-1,1'-binaphthyl gives excellent results in asymmetric hydrogenation of .beta.-ketoesters.
However, since their selectivity (chemical selectivity or enantio-selectivity) and catalytic activities are not sufficient depending on the intended reactions or reaction substrates thereof, there are cases in which these catalysts have to be improved.